In recent years, with the speeding-up of optical signals in a trunk system, it has been needed to process optical signals at ultrahigh-speeds also in an optical switching function, such as, an optical cross-connecting device or the like. Further, the switching scale has also been significantly large due to an increase of wavelength division multiplexing numbers in a wavelength division multiplexing (WDM) transmission technology.
Under such backgrounds, as one of relatively large scale optical switches, the development of a wavelength selective switch (WSS) has been progressed. The wavelength selective switch is an optical device capable of selectively inputting or outputting arbitrary wavelengths, and a fiber collimator array is used as input/output ports thereof. Such a fiber collimator array includes, for example: a fiber array in which a plurality of optical fibers is arrayed to correspond to the input and output ports; and a microlens array in which respective microlenses are arrayed on positions corresponding to the respective optical fibers.
Here, if an optical axis of each optical fiber and an optical axis of each microlens are deviated from each other, an insertion loss of the wavelength selective switch is increased. Therefore, there has been known a configuration in which each microlens is precisely aligned with each optical fiber to thereby configure the fiber collimator array. In a technology disclosed in Japanese Unexamined Patent Publication No. 2007-328177, an optical fiber array block making up the fiber array and a silica microlens mounting base (to be simply referred to as a mounting base, hereunder) making up the microlens array are integrated with each other, and optimum positions on the mounting base are searched, so that respective microlenses are adhered to the optimum positions on the mounting base.
However, since each microlens is significantly small, the adhesive intensity thereof is low by being simply adhered to the mounting base, and therefore, there is a possibility that a resistance to vibration or a resistance to impact cannot be sufficiently ensured. Further, each microlens may be required to be subjected to extremely minute position adjustment, and therefore, it is also necessary to adopt a configuration in which such position adjustment can be easily performed, that is, a configuration in which each microlens is easily moved on the mounting base.
The above described problems are common to optical components each having an adhesive structure in which a relatively small optical member (first optical member) is adhered to another optical member (second optical member).